﻿/*
 * Greenshot - a free and open source screenshot tool
 * Copyright (C) 2007-2016 Thomas Braun, Jens Klingen, Robin Krom
 * 
 * For more information see: http://getgreenshot.org/
 * The Greenshot project is hosted on GitHub https://github.com/greenshot/greenshot
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 1 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
using System;
using Greenshot.Drawing;
using Greenshot.Plugin.Drawing;

namespace Greenshot.Memento {
	/// <summary>
	/// The AddElementMemento makes it possible to undo adding an element
	/// </summary>
	public class AddElementMemento : IMemento  {
		private IDrawableContainer _drawableContainer;
		private Surface _surface;
		
		public AddElementMemento(Surface surface, IDrawableContainer drawableContainer) {
			_surface = surface;
			_drawableContainer = drawableContainer;
		}

		public void Dispose() {
			Dispose(true);
			GC.SuppressFinalize(this);
		}

		protected virtual void Dispose(bool disposing) {
			//if (disposing) { }
			_drawableContainer = null;
			_surface = null;
		}

		public bool Merge(IMemento otherMemento) {
			return false;
		}

		public IMemento Restore() {
			// Before
			_drawableContainer.Invalidate();
			// Store the selected state, as it's overwritten by the RemoveElement

			DeleteElementMemento oldState = new DeleteElementMemento(_surface, _drawableContainer);
			_surface.RemoveElement(_drawableContainer, false);
			_drawableContainer.Selected = true;

			// After
			_drawableContainer.Invalidate();
			return oldState;
		}
	}
}
